The present invention relates to a novel class of flotation agents, namely the hydrocarbyl bicarbonates as flotation reagents in the separation of earth alkaline metal minerals, such as of magnesium, calcium, strontium, and barium, as well as base metal minerals such as of copper, silver, lead, and zinc, also heavy metal minerals such as of nickel, cobalt, iron, and manganese.
Flotation is a process of treating a mineral slurry of a pulverulent ore suspended in water; an ore in which the mineral of a certain metal which is to be recovered is substantially liberated from the gangue minerals, such as clay, silica, silicates and the like; a process in which certain chemicals are added to the pulp of mineral slurry, and by introducing the air by blowing or agitation, because of which a froth mass containing bubbles is produced; said bubbles may develop only by certain chemicals, commonly known as frothers or collector-frothers, to which adhere the finely divided mineral particles of mineral to be recovered, and leaving suspended (unfrothed) other solid components of the ore. Thus, flotation is based on the principle that introducing chemical and the air into water containing solid particles of different materials suspended therein which causes adherence of air to certain suspended solid and to make the particles having air bubbles thus adhered thereto lighter than the water. Accordingly, they rise to the top of the water to form a froth, which as such is skimmed off.
Various flotation agents have been admixed with the suspension to improve the frothing as well as the collecting process. Such added agents are classed according to the function to be performed: frothers which impart the property of forming a stable froth, e.g., natural oils such as pine oil and eucaliptus oil, or industrial products such as cresylic acid, higher alcohols, ethoxylated aliphatic and aromatic hydrocarbons and the like products; collectors such as xanthates, thiocarbamates, cresyl thiophosphates and the like. Besides the enumerated frothers and collectors, certain chemical compounds are added to the mineral slurry to enhance the phenomena of flotation and advantageously influence the separation of desired mineral, or depress the undesired components of the ore. Thus, emulsifiers, dispersants, depressants, and modifiers are added.
It is important to bear in mind that additives of the above type are selected for use according to the nature of the ore, the mineral sought to be recovered, and the other additaments which are to be used in combination therewith.
An understanding of the phenomena which makes flotation a particularly valuable industrial operation is not essential to the practice of the present invention. They appear, however, to be largely associated with selective affinity of the surface of particulated solids suspended in water containing entrapped air, for the water on one hand, the air on the other.
Flotation principle is applied in a number of mineral separation processes among which the selective separation of such minerals as sulfide copper minerals, sulfide lead mineral, sulfide zinc mineral, sulfide molybdenum mineral and other sulfides from sulfide iron minerals. The present invention concerns a novel class of compounds namely the alkyl, alkylaryl, aralkyl, aryl, cyclo, and cycloalkyl bicarbonates. These compounds can be employed as collecting agents in flotation process. With some of these compounds better recoveries are realised and with others, improved selectivity is achieved. Certain of these compounds produce improvements in both aspects not only with some of the preceding sulfides but with certain oxide minerals also.